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Chinese Journal of Chemical Engineering 2024年第7期71卷 77-90页

作者： Dandan Ren Jiale xie Tianle Chen Haibin Qu Xingchu Gong Pharmaceutical Informatics Institute College of Pharmaceutical SciencesZhejiang UniversityHangzhou 310058China National Key Laboratory of Chinese Medicine Modernization Zhejiang UniversityHangzhou 310058China Jinhua Institute of Zhejiang University Jinhua 321016China

The current methods used to industrially produce sinomenine hydrochloride involve several issues,including high solvent toxicity,long process flow,and low atomic utilization efficiency,and the greenness scores of the processes are below 65 *** solve these problems,a new process using anisole as the extractant was *** exhibits high selectivity for sinomenine and can be connected to the subsequent water-washing *** alkalization of the medicinal material,heating extraction,water washing,and acidification crystallization were carried *** process was modeled and *** design space was *** recommended operating ranges for the critical process parameters were 3.0–4.0 h for alkalization time,60.0–80.0℃ for extraction temperature,2.0–3.0(volume ratio)for washing solution amount,and 2.0–2.4 mol·L^(-1) for hydrochloric acid *** new process shows good robustness because different batches of medicinal materials did not greatly impact crystal purity or sinomenine transfer *** sinomenine transfer rate was about 20%higher than that of industrial *** greenness score increased to 90 points since the novel process proposed in this research solves the problems of long process flow,high solvent toxicity,and poor atomic economy,better aligning with the concept of green chemistry.

关键词： Sinomenine hydrochloride Process optimization Anisole

Application of Optical Hydrogels in Environmental Sensing

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Energy & Environmental Materials 2024年第3期7卷 311-336页

作者： Shuo Yang Shruti Sarkar Xing xie Dan Li Jianmin Chen Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention(LAP3) Department of Environmental Science and EngineeringFudan UniversityShanghai 200438China School of Civil and Environmental Engineering Georgia Institute of TechnologyAtlanta Georgia 30332USA

The ever-increasing complexity of environmental pollutants urgently warrants the development of new detection *** based on the optical properties of hydrogels enabling fast and easy in situ detection are attracting increasing *** this paper,the data from 138 papers about different optical hydrogels(OHs)are extracted for statistical *** detection performance and potential of various types of OHs in different environmental pollutant detection scenarios were evaluated and compared to those obtained using the standard detection *** on this analysis,the target recognition and sensing mechanisms of two main types of OHs are reviewed and discussed:photonic crystal hydrogels(PCHs)and fluorescent hydrogels(FHs).For PCHs,the environmental stimulus response,target receptors,inverse opal structures,and molecular imprinting techniques related to PCHs are reviewed and ***,the different types of fluorophores(i.e.,compound probes,biomacromolecules,quantum dots,and luminescent microbes)of FHs are ***,the potential academic research directions to address the challenges of applying and developing OHs in environmental sensing are proposed,including the fusion of various OHs,introduction of the latest technologies in various fields to the construction of OHs,and development of multifunctional sensor arrays.

关键词： environmental sensors fluorescent hydrogel optical hydrogel photonic crystal hydrogel pollution detection

Influence of Vanes and Blades on Ingress in Axial Rim Seal for Turbine Stages

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Journal of Thermal Science 2024年第3期33卷 833-846页

作者： REN Ran DU Qiang LIU Guang ZENG Yanlian xie Lei Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing100190China National Key Laboratory of Science and Technology on Advanced Light-duty Gas-turbine Beijing100190China School of Aeronautics and Astronautics University of Chinese Academy of SciencesBeijing100190China

Hot gas ingestion refers to the phenomenon of mainstream hot gas flowing into the space cavity of a turbine *** studies have found that mainstream annulus pressure distribution plays an important role in hot gas ingestion,but due to its complexity,the mechanism of the interaction between mainstream flow and hot gas ingestion remains *** paper adopts the URANS method,and three sealing flow rates are considered,named C_(w)=0,C_(w)=500,and C_(w)=*** time-averaged annulus pressure distribution shows that an increase in the sealing flow decreases the pressure value,and the effects of the sealing flow on the pressure distribution of the leading edge of the blade are much more influential than that of the trailing edge of the *** unsteady pressure time-space distribution in the annulus indicates that a time-space tilted distribution of pressure at the rim exits when the sealing flow *** phenomenon is mainly due to the strong feedback mechanism of the sealing flow to the annulus pressure field.A comparison of the pressure and mean radial velocity distribution of the mainstream shows that the ingestion mainly occurs on the blade side,where the pressure is lower than on the vane *** flow characteristics at the wheel rim are analyzed with a sealing flow rate C_(w)=5000,and under these conditions,both pressure-induced ingestion and ingestion caused by a passage vortex can be *** three-dimensional and inertial effects of the mainstream at the wheel rim lead to the generation of separation vortices on the blade side,and the presence of separation vortices leads to ingestion along the blade *** the same time,pressure on the blade side will cause the fluid to have a radial inward flow tendency,which will promote the formation of separation vortices,leading to more serious ingestion in the high-pressure region on the blade *** blade pressure field can be more significant than the vane trailing pressure field in the rim sea

关键词： separation vortex unsteady rim seal the effect of blade on ingestion

Tough lanthanide luminescent hydrogel for nitroaromatics detection

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Journal of Rare Earths 2024年第2期42卷 293-302,I0003页

作者： Shu xie Fei Li Fengyi Liu Quanqing Xu Xufeng Zhang College of Chemistry and Chemical Engineering Yunnan Normal UniversityKunming650092China

Luminescent hydrogels have received considerable attention in the application of *** matics are harmful to human health and can be *** skin allergies and central nervous system injuries may also be attributed to the over exposure to ***,nitroaromatics sensor with fast detection and low detection limit is highly ***,novel tough hydrogels were prepared by introducing hydrogen bonds and covalent bonds into the interpenetrating networks of modified chitosan and poly(vinyl alcohol)(PVA) via frozen-thawing induced chemical *** synthesized hydrogels exhibit high mechanical strength(0.23 MPa tensile strength at 140% tensile strain,1.0 MPa compressive strength at 80% compressive strain).Strong green emission was realized by energy transfer from the modified chitosan to Tb^(3+)via the so-called "antenna effect." The prepared luminescent hydrogels show an excellent detection effect on nitroaromatic compounds and its detection limit can reach *** hydrogels also exhibit good reversibility and a fast "off-on" fluorescence switching *** work may open up a new way for the development of stable,rapid,and reusable sensors for the detection of harmful nitroaromatics.

关键词： Hydrogels Lanthanide Luminescence Nitroaromatics Sensors Rare earths

Giant low-field reversible magnetocaloric effect at liquid helium temperature of niobium and iron co-substituted EuTiO_(3) compounds

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Journal of Rare Earths 2024年第4期42卷 710-715页

作者： Zhihong Hao Quanyi Liu Huicai xie Yan Zhang Zhaojun Mo School of Rare Earth and New Materials Engineering Ganzhou Innovation Center of Rare Earth Permanent Magnet Material Advanced Manufacturing and Intelligent Equipment TechnologyGannan University of Science and TechnologyGanzhou341000China Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou34119China School of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan030024China

Giant magnetocaloric effect(MCE)materials in the liquid helium temperature region have attracted a lot of attention in the field of low-temperature magnetic refrigeration(MR).In this study,a series of niobium(Nb)and iron(Fe)co-substituted EuTiO_(3) perovskites with cubic structure(space group pm3m)was successfully fabricated,and their magnetic properties as well as cryogenic magnetocaloric effects were investigated in *** expected,the introduction of Nb and Fe can significantly modulate the magnetic phase transition and magnetocaloric effect of the EuTiO_(3) *** increasing Fe concentration,two local minima corresponding to the AFM-FM magnetic phase transition near 5.0 K and FM-PM transition near 10 K with no hysteresis in the thermomagnetic curves are observed,which is attributed to an enhancement of FM *** the same time,the gradually widened-ΔSM-T curves and the two peaks with a broad shoulder lead to considerable refrigeration capacity(RC).With the field change ofΔH=2 T,the calculated values of-ΔS_(M)^(max) for the EuTi_(0.9375-x)Nb_(0.0625)Fe_(x)O_(3)(x=0.075,0.1,0.125,0.15)compounds are 24.2,17.6,14.5 and 14.0 J/(kg·K),*** corresponding RC values were calculated to be 144.6,138.3,151.2 and 159 J/kg,***,the values of-ΔS_(M)^(max) for EuTi_(0.8625)Nb_(0.0625)Fe_(0.075)O_(3) are 8.6 and 15.1 J/(kg·K)under low field changes of 0.5 and 1 T,*** giant low-field reversible magnetocaloric effect makes them attractive candidates for magnetic refrigeration in the liquid helium temperature region.

关键词： Magnetocaloric effect Refrigeration capacity Magnetic entropy change Rareearths

Experimental investigation about the incipient velocity of spherical particles on a hemispherical bed surface

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Particuology 2024年第5期88卷 49-61页

作者： Chuannan Li Jie Chen changbo Jiang xie Li Zhiyuan Wu School of Hydraulic and Environmental Engineering Changsha University of Science & TechnologyChangsha 410114China Key Laboratory of Dongting Lake Aquatic Eco-Environmental Control and Restoration of Hunan Province Changsha 410114China Key Laboratory of Water-Sediment Sciences and Water Disaster Prevention of Hunan Province Changsha 410114China

The sediment particles play a huge role in shaping the bed load *** this research,240 water-tunnel experiments are carried out to investigate the incipient velocity of the observation particles in two particle *** accurately predict the incipient velocity of the observation particles,the equation is conceived by the rolling instability *** incipient velocity equations and experimental data are used to analyze the trend of dispersive pressure and the effect of arrangement position on *** find that it is appropriate to choose the coefficient of drag as 0.261 and the coefficient of lift as 0.198 for the incipient velocity equation of spherical particles on the hemispherical bed ***,the dispersive pressure is closely related to the flow state,particle size,and particle arrangement,which leads to the incipient velocity of the observation particle being at a minimum when the interference particle angle is 45°.Finally,the particle spacing and the projected area changed with the arrangements,directly affecting the incipient velocity of the observed *** analysis of four aspects for the coefficients,dispersive pressure,different particle spacing,and projected area will facilitate the prediction of particle incipient velocity,especially on hemispherical beds.

关键词： Hemispherical bed surface Observed particle Interference particle Dispersive pressure Incipient velocity

Puerarin mediated miR-30b-5p targeting fibroblast activation protein against oral submucous fibrosis

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BIOCELL 2024年第4期48卷 591-599页

作者： SAIFEI xie HUI xie JINCAI GUO JIN TAN YULIN YU MINYI ZHANG SHANG WEN Department of Periodontal Mucosa Hunan University of Chinese MedicineChangshaChina Department of Periodontal Mucosa Changsha Stomatology HospitalChangshaChina Department of Pharmacy Changsha Stomatology HospitalChangshaChina Department of Stomatology The First Hospital of Hunan University of Chinese MedicineChangshaChina

Background:Puerarin(Pue)has been reported to be a natural active ingredient with multiple antiﬁbrotic *** work aimed at exploring the function of Pue in oral submucousﬁbrosis(OSF)***:Human oral mucosaﬁbroblasts(hOMF)were induced with transforming growth factor beta1(TGF-β1)and intervened with *** ofﬁbrosis-related markers were analyzed by Western blot and IF *** viability was characterized by the CCK-8 *** of miR-30 family members were quantiﬁed by *** correlation betweenﬁbroblast activation protein(FAP)and miR-30 family expression was evaluated by the Pearson correlation coefﬁ*** prediction and dual-luciferase reporter assay were employed to verify the regulation between FAP and *** speciﬁc mechanism of Pue on OSF was explored through the promotion or inhibition of ***:After induction by TGF-β1,hOMF showed upregulated Collagen I,Collagen III,and FAP expressions,while miR-30 family expression was downregulated with miR-30b-5p being the most signiﬁ*** intervention inhibited the excessive proliferation of TGF-β1-induced hOMF,downregulated FAP,collagen type 3(COL3A1),collagen type 1(COL1A1),matrix metalloproteinase 1(MMP1),and matrix metalloproteinase 3(MMP3)expressions,and restored miR-30 family *** prediction and dual-luciferase reporter assay revealed that miR-30b-5p selectively inhibited FAP ***,miR-30b-5p mimic suppressed the excessive proliferation of TGF-β1-induced hOMF and declinedﬁbrosis *** intervention signiﬁcantly reversed the promotion of TGF-β1-induced OSF by miR-30b-5p ***:Pue mediated miR-30b-5p targeting FAP against OSF,which provided a theoretical basis for the pathogenesis research and Pue application in OSF.

关键词： Puerarin miR-30b-5p FAP Oral submucous fibrosis

Maximum Power Point Tracking Technology for PV Systems: Current Status and Perspectives

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Energy Engineering 2024年第8期121卷 2009-2022页

作者： Bo Yang Rui xie Zhengxun Guo Faculty of Electric Power Engineering Kunming University of Science and TechnologyKunming650500China Intelligent Electric Power Grid Key Laboratory of Sichuan Province Chengdu610065China Foshan Graduate School of Innovation Northeastern UniversityFoshan528311China College of Information Science and Engineering Northeastern UniversityShenyang110819China

Maximum power point tracking(MPPT)technology plays a key role in improving the energy conversion efficiency of photovoltaic(PV)systems,especially when multiple local maximum power points(LMPPs)occur under partial shading conditions(PSC).It is necessary to modify the operating point efficiently and accurately with the help of MPPT technology to maximize the collected *** though a lot of research has been carried out and impressive progress achieved for MPPT technology,it still faces some challenges and ***,the mathematical model established for PV cells is not precise ***,the existing algorithms are often optimized for specific conditions and lack comprehensive adaptability to the actual operating ***,a single algorithm may not be able to give full play to its *** the end,the selection criteria for choosing the suitable MPPT algorithm/converter combination to achieve better performance in a given scenario is very ***,this paper systematically discusses the current research status and challenges faced by PV MPPT technology around the three aspects of MPPT models,algorithms,and hardware *** in-depth thinking and discussion,it also puts forward positive perspectives on future development,and five forward-looking solutions to improve the performance of PV systems MPPT are suggested.

关键词： PV systems MPPT partial shading condition DC-DC converter

Learning Dual-Layer User Representation for Enhanced Item Recommendation

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Computers, Materials & Continua 2024年第7期80卷 949-971页

作者： Fuxi Zhu Jin xie Mohammed Alshahrani Applied Research Center of Artificial Intelligence Wuhan CollegeWuhan430212China College of Computer Science South-Central MINZU UniversityWuhan430074China Unmanned.Company Riyadh11564Saudi Arabia

User representation learning is crucial for capturing different user preferences,but it is also critical challenging because user intentions are latent and dispersed in complex and different patterns of user-generated data,and thus cannot be measured ***-based data models can learn user representations by mining latent semantics,which is beneficial to enhancing the semantic function of user ***,these technologies only extract common features in historical records and cannot represent changes in user ***,sequential feature can express the user’s interests and intentions that change time by *** the sequential recommendation results based on the user representation of the item lack the interpretability of preference *** address these issues,we propose in this paper a novel model with Dual-Layer User Representation,named DLUR,where the user’s intention is learned based on two different layer ***,the latent semantic layer adds an interactive layer based on Transformer to extract keywords and key sentences in the text and serve as a basis for *** sequence layer uses the Transformer model to encode the user’s preference intention to clarify changes in the user’s ***,this dual-layer user mode is more comprehensive than a single text mode or sequence mode and can effectually improve the performance of *** extensive experiments on five benchmark datasets demonstrate DLUR’s performance over state-of-the-art recommendation *** addition,DLUR’s ability to explain recommendation results is also demonstrated through some specific cases.

关键词： User representation latent semantic sequential feature interpretability

Unlocking stability:Preserving activity of biomimetic catalysts with covalent organic framework cladding

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Chinese Chemical Letters 2024年第6期35卷 1-2页

作者： Ting Wang Xin Yu Yaqiang xie College of the Environment&Ecology Xiamen UniversityXiamen 361102China

Enzymes are extremely complicated biocatalysts in several industrial processes due to their numerous advantages over conventional catalysts,including lower physiological and environmental toxicity,exceptional selectivity,and milder reaction conditions[1].However,their widespread applications are constrained by the high production costs,low operational stability,and complexity involved in the recovery and reusability of enzymes[2].

关键词： stability catalysts exceptional